The reaction pathways of 1-propanethiol, 1-propanol, and propylamine molecules, containing a propyl moiety, on a Ge(100) surface were investigated using high-resolution photoemission spectroscopy (HRPES) experiments and density functional theory (DFT) calculations. Upon analysis of the HRPES data, the adsorption of 1-propanethiol and 1-propanol was found to occur through a dissociation reaction, whereas that of propylamine took place via N dative bonding at room temperature. On the basis of our DFT results, adsorption geometries and transition states for each of these molecules on the Ge(100) surface were confirmed. Systematic studies of S-, O-, and N-containing molecules, composed of an identical propyl moiety, on the Ge(100) surface provide insight into the adsorption mechanism of aliphatic molecules containing alkyl chains on the Ge(100) surface.

The sputtering yield of tungsten pellets composed of different particle sizes of <1, 12, 44–74, and 149–297 μm was systematically investigated by bombardment with Ar+ ions accelerated at 2.0 keV in an ultra-high vacuum chamber. We found that the tungsten sample fabricated from larger particles had a higher surface roughness, based on the surface profile results. Using the data of the surface roughness for the four types of tungsten pellets, we confirmed that the sputtering yield for a tungsten pellet with the highest surface roughness was 7 times lower than that of the lowest surface roughness. This could be due to the redeposition of sputtered tungsten particles onto neighboring asperities.

This study explored the crystallographic characterization of zirconium, zirconium-based samples containing minor alloying elements, simulated Zircaloy-4, and simulated ZIRLO at a temperature range of 30–870 °C using in situ high-temperature X-ray diffraction. The results from Pawley refinement demonstrated that the lattice thermal expansion along the a-axis direction is suppressed by the tin element, in contrast to the other minor alloying elements. Moreover, the simulated ZIRLO possesses the enhanced resistance for lattice thermal expansion compared to the simulated Zircaloy-4, indicating that a ZIRLO cladding has a better performance in suppressing the change in the lattice constants under a thermal environment.

The adsorption structures and reaction mechanism of tetrahydrofuran on a Ge(100) surface were investigated through high-resolution photoemission spectroscopy (HRPES) and density functional theory (DFT) calculations. On the basis of our analysis of the HRPES spectra, two adsorption species consisting of a major Ge-(CH2)4-O-Ge structure formed via a ring-opening reaction and a minor molecularly adsorbed structure formed via O dative bonding were identified. Our DFT results provided not only the optimized adsorption structures and their corresponding adsorption energies but also the level of the transition state for the pathway from the molecularly adsorbed species to the major adsorption structure. The results confirmed that the adsorption of tetrahydrofuran on the Ge(100) surface is under both kinetic and thermodynamic controls. Our discovery of the ring-opening reaction is an unprecedented result in the field of Ge(100) surface chemistry.

The coverage and temperature dependence of ZIRLO cladding with H 2 O adsorption are studied using synchrotron-based high-resolution photoemission spectroscopy (HRPES). Based on the analytical results of the Zr 3 d , O 1 s , C 1 s , and Sn 3 d HRPES profiles prior to H 2 O adsorption, we determine the surface compositions of O 2− , hydroxyl OH − , chemisorbed H 2 O, zirconium carbide, adventitious carbon, Sn metal, and SnO 2 in ZIRLO. When ZIRLO is exposed to H 2 O molecules, the relative proportion of zirconium metal decreases, whereas that of the total zirconium oxides increases, suggesting the reaction between H 2 O and the zirconium metal in ZIRLO. On annealing a sample with 1000 L H 2 O on ZIRLO at 300 °C, Zr 2 O 3 and ZrO 2 decompose, and oxygen diffuses into the bulk, thereby reducing the oxidation states of zirconium on the surface. Moreover, at this temperature, the excess H 2 O molecules on ZIRLO are thoroughly desorbed and tin element is diffused into the bulk in ZIRLO.